Polyelectrolyte multilayer (PEM) thin films consisting of alternate layers of two PEM systems, that is poly(diallyl dimethyl ammonium chloride)/poly(vinyl sulfate) (PDAC/PVS) and poly(allyl amine hydrochloride) (PAH)/ are successfully deposited on polysulfone (PSF) support using spin-assisted layer-by-layer assembly. The films are characterized using atomic force microscope, Fourier transform Infrared, and contact angle measurement. The salt (NaCl) rejection and water flux of the [PDAC/PVS] and [PAH/PVS] membranes are also evaluated using a crossflow permeation test cell. The permeation test shows that 120 bilayers of [PAH/PVS] on PSF substrate provide salt rejection of 53% and water flux of 37 L/m2 h, whereas that of PDAC/PVS on PSF substrate provide salt rejection of 21% and water flux of 90 L/m2 h for a 2000-ppm NaCl solution feed at a pressure of 40 bar and temperature of 25 degrees C. (c) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012